Additional survival benefit of bilateral in situ internal thoracic artery grafting with composite radial artery graft in total arterial off-pump coronary artery bypass grafting

Objective: This study aimed to elucidate whether the use of bilateral internal thoracic arteries (BITAs) confers additional survival benefits compared with a single internal thoracic artery (SITA) in total arterial grafting with the radial artery.Methods: Between 2002 and 2016, 617 patients underwent a bilateral in situ inter-nal thoracic artery grafting with the radial artery as a composite I-graft (BITA-I group) and 516 patients underwent single in situ internal thoracic artery grafting with the radial artery as a composite Y-graft (SITA-Y group). All anastomoses were performed without cardiopulmonary bypass and aortic manipulation. Propen-sity score matching was performed to adjust covariates and compared the out-comes between the 2 groups. Subanalysis was also performed to evaluate the effects of the BITA-I group on survival according to the covariates using Cox pro-portional hazards regression analysis.Results: Propensity score matching yielded 348 well-matched pairs. Early postop-erative outcomes were similar in the 2 groups. The BITA-I group showed signifi- cantly better survival than the SITA-Y group (79.3% vs 70.2% at 10 years, P 1/4 .015). The subanalysis revealed a significantly better survival in the BITA-I group among overall patients (hazard ratio, 0.68; 95% confidence interval, 0.49-0.93). There was a significant positive effect on survival in the BITA-I group among pa-tients without comorbidities or those aged <77 years.Conclusions: BITA grafting with the radial artery provides better long-term survival than SITA grafting with the radial artery, which is enhanced among patients aged <77 years with minimum comorbidities. (J Thorac Cardiovasc Surg 2023;166:519-29)